Nodular lymphoid hyperplasia of the gastrointestinal tract is characterized by the presence of multiple small nodules, normally between between 2 and 10 mm in diameter, distributed along the small intestine (more often), stomach, large intestine, or rectum. The pathogenesis is largely unknown. It can occur in all age groups, but primarily in children and can affect adults with or without immunodeficiency. Some patients have an associated disease, namely, common variable immunodeficiency, selective IgA deficiency, Giardia infection, or, more rarely, human immunodeficiency virus infection, celiac disease, or Helicobacter pylori infection. Nodular lymphoid hyperplasia generally presents as an asymptomatic disease, but it may cause gastrointestinal symptoms like abdominal pain, chronic diarrhea, bleeding or intestinal obstruction. A diagnosis is made at endoscopy or contrast barium studies and should be confirmed by histology. Its histological characteristics include markedly hyperplasic, mitotically active germinal centers and well-defined lymphocyte mantles found in the lamina propria and/or in the superficial submucosa, distributed in a diffuse or focal form. Treatment is directed towards associated conditions because the disorder itself generally requires no intervention. Nodular lymphoid hyperplasia is a risk factor for both intestinal and, very rarely, extraintestinal lymphoma. Some authors recommend surveillance, however, the duration and intervals are undefined.
Keywords: Adults; Endoscopy; Gastrointestinal tract; Lymphoma; Nodular lymphoid hyperplasia.